1. EU-Regulation Number 510/2011https://eur-lex.europa.eu/legal-content/EN/TXT/?uri=celex%3A32011R0510
2. Gesetz zur Änderung der Förderung von Biokraftstoffen, 19 July 2009https://www.bgbl.de/xaver/bgbl/start.xav?start=%2F%2F*[%40attr_id%3D%27bgbl109s1804.pdf%27]#__bgbl__%2F%2F*%5B%40attr_id%3D%27bgbl109s1804.pdf%27%5D__1541147863998
3. Hart Energy Publishing and its Global offices, Bio-ETBE: The Right Road to High Quality 21st Century Motor Fuelshttps://de.scribd.com/document/148045860/ 2008-Hart-Publication-on-Bio-ETBE.